1,2,4‐Oxadiazole[4,5‐a]piridinium salts add alcohols and alkoxides to undergo electrocyclic ring opening affording alkoxybutadienyl 1,2,4‐oxadiazole derivatives. The pyridinium salts represent a special class of Zincke salts that are prone to rearrange to give alkoxybutadienyl 1,2,4‐oxadiazoles when treated with suitable nucleophiles or, alternatively, to give pyridones in the presence of bicarbonate. The pivotal tuning of the experimental conditions leads to a straightforward synthesis of valuable 1,2,4‐oxadiazole derivatives. The mechanism is also discussed in the light of previous observations.

中文翻译：

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1,2,4-恶二唑[4,5-a]吡啶鎓盐与醇的反应：烷氧基丁二烯基1,2,4-恶二唑的合成。

1,2,4-恶二唑[4,5- a ]吡啶鎓盐加成醇和醇盐进行环电开环，得到烷氧基丁二烯基1,2,4-恶二唑衍生物。吡啶鎓盐代表一类特殊的Zincke盐，当用合适的亲核试剂处理时，倾向于重排生成烷氧基丁二烯基1,2,4-恶二唑，或者在存在碳酸氢盐时生成吡啶酮。实验条件的关键调整可直接合成有价值的1,2,4-恶二唑衍生物。还根据先前的观察结果讨论了该机制。